The protest is also affecting car traffic traveling over the St. John Bridge.

Federal permits allowing Royal Dutch Shell to drill for oil require the Fennica to be on site in Alaska’s Chukchi Sea.

Climate change activists gathered in North Portland on Tuesday, launching kayaks into the Willamette River to get in the Fennica’s way.

Shell spokesman Curtis Smith told OPB that the Fennica will begin its return journey to Alaska once final preparations are complete. Smith says the company respects the choice of people to protest. He did not indicate when the ship is expected to depart.

According to the Columbia River Bar Pilots website, The Fennica was scheduled to depart early Wednesday. That was rescheduled for noon before its departure time was removed from the website Wednesday afternoon, with the icebreaker remaining at Vigor Industrial’s dry dock.

Organizer Michael Gaskill, with Portland Rising Tide, said his goal was to delay the ship and to tell Shell that drilling in the Arctic is immoral.

“I am personally willing to risk arrest for this. I feel like this is one of the most important issues of our time,” Gaskill said.

Pete Simpson with Portland Police said that officers are monitoring the protestors, for now.

“Dangling off the bridge is against the law,” said Simpson. “There are trespassing laws that would apply. And I believe other statutes that would apply. Our hope is that people will demonstrate peacefully and that they are not in a position to interfere with river traffic.”

Simpson said Portland Police are coordinating operations along with the county sheriff’s office and the Coast Guard

A spokesman for the U.S. Coast Guard said people need to stay at least 500 yards away from the front of the Fennica when it’s underway.

Officers will warn people who enter the safety zone, and then remove them physically if necessary. Violators could face a $500 fine.

An official with Shell said its Arctic drilling plan has passed a thorough federal environmental review, even as it has faced protests in Portland and other Northwest cities. The company said global energy use will double by the year 2050, and the reserves off Alaska’s coast could help meet that demand.